If a slave carries out his duties towards his master, serving and obeying him in what is good and being sincere to him, and performs the obligations and shuns the prohibitions laid down by Allah, the Almighty, he shall have a double reward on the Day of Judgment. This is because he is under two obligations: 1. To fulfill the rights of his master, and if he does so, he will get a reward. 2. To obey his Lord, and if he does so, he will get a reward.